1. Technical Field
The present invention relates to a crimping terminal which is mostly used as a connector terminal.
2. Background Art
A typical crimping terminal has a front part having an electric connection portion for connection to a counterpart terminal or the like, and a rear part having an electric wire connecting portion adapted to be crimped and connected to an end portion of an electric wire. The wire connecting portion is usually configured such that a conductor crimping portion is disposed on the front side and a sheath fastening portion is disposed on the rear side with a space provided therebetween.
In this type of crimping terminals, a terminal having two members made of dissimilar metal materials provided separately and then put together is known, examples thereof are described in, for example, JP 10-050377 A and JP 2004-199934 A.
FIGS. 5A and 5B illustrate a configuration of a female side terminal fitting (crimping terminal) described in JP 10-050377 A. The female side terminal fitting includes a terminal body 82, provided as a single piece, having an electric wire connecting portion (a conductor crimping portion 82A and a sheath fastening portion 82B) to which an end portion of an electric wire is fixed and a contact portion 82D operable to contact a counterpart male side terminal fitting, and a terminal fitting auxiliary member 81 made of a metal material having higher elasticity than the terminal body 82, joined to the terminal body 82, and having an elastic contact piece 81D which presses the counterpart male side terminal fitting against the contact portion 82D.
An insert portion 82C which is inserted into a box portion 81A of the terminal fitting auxiliary member 81 is provided at the front of the terminal body 82 (the side in contact with the terminal fitting auxiliary member 81), and the contact portion 82D is provided above the insert portion 82C. The elastic contact piece 81D of the terminal fitting auxiliary member 81 is disposed inside the box portion 81A. After the terminal fitting auxiliary member 81 and the terminal body 82 are assembled, and a fixing piece 85 of the terminal fitting auxiliary member 81 is crimped onto a fixing portion 86 of the terminal body 82, whereby the elastic contact piece 81D and the contact portion 82D face each other, and the male side terminal fitting of the counterpart connector is received between the elastic contact piece 81D and the contact portion 82D.
In this crimping terminal, the terminal fitting auxiliary member 81 having the elastic contact piece 81D is made of a material having higher elasticity than the terminal body 82, whereby it is possible to increase contact pressure against the counterpart male side terminal fitting.
JP 2004-199934 A describes a connector terminal which has a conductor joining portion joined with a conductor of an aluminum electric wire and a terminal connecting portion electrically connectable to a counterpart terminal. In this connector terminal, the conductor joining portion and the terminal connecting portion are integrally formed using an aluminum-based material, an elastic biasing member which elastically biases the counterpart terminal toward the terminal connecting portion when the terminal connecting portion is connected to the counterpart terminal is molded using an iron-based metal material, and the aluminum-based material and the iron-based metal material are connected together such that the molded terminal connecting portion and elastic biasing portion are joined together.
In this terminal, because the conductor joining portion is formed using the aluminum-based material, and the elastic biasing portion is formed using the iron-based metal material, it is possible to increase contact pressure when being connected to the counterpart terminal while avoiding a problem of electric corrosion when being connected to the aluminum electric wire.
On the other hand, with the conventional terminals described in JP 10-050377 A and Patent Document 2, the two members made of dissimilar metal materials are joined together, but the joined portions remain exposed. Thus, when water adheres to this portion, electric corrosion may occur at the joined portions.